Heated creeper



Aug. 2 3, 1955 F. o. RITTER HEATED CREEPER 2 Sheets-Sheet 1 Filed Dec.14, 1954 /6 Fig. 2

Ferris 0. Hitter United States Patent HEATED CREEPER Ferris O. Ritter,Detroit, Mich.

Application December 14, 1954, Serial No. 475,093

4 Claims. (Cl. 219-19) This invention relates to devices designated asmechanics work creepers and is more specifically concerned withproviding a heated mechanics work creeper which makes it possible forthe mechanic to be more comfortable while working in damp or frigidplaces, and protecting the health of the mechanic utilizing this device.

Electrically heated work creepers prior to this invention, to the bestof present knowledge, had serious drawbacks, to the extent of beingdangerous to the user. Generally, these work creepers were constructedof metal plates. Inasmuch as the electrically heated creeper wasgenerally used during intemperate weather, i. e., when snow and rainwould accumulate as excess water on the floor of a garage, and inasmuchas the creeper is relatively close to the ground level, the danger ofthe shorting out of the creeper and hence shocking the operator of thedevice was always present. In addition to the aforementioned danger,electrical work creepers of the past, to the best of present knowledge,required. constant adjustment after they heated up or failed to providesufficient heat. The constant necessity for manually adjusting the heatoutput of the electrically heated creeper provided a source ofinterruption to the relatively high paid mechanic as well as a constantsource of irritation.

Thus, a principal object of this invention is to provide an electricallyheated work creeper providing a constant and safe heat output.

A further object of this invention is to provide an electrically heatedwork creeper including an automatically controlled heat outputminimizing danger from electrical shock to the operator or user of thedevice.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

Figure 1 is a perspective view of the novel work creeper;

Figure 2 is an enlarged sectional view taken on line 2-2 of Figure 1;

Figure 3 is an enlarged longitudinal sectional view taken on line 3-3 ofFigure 1, the central portion of which is not being shown;

Figure 4 is a top plan view on a somewhat reduced scale, with partsbroken away to show internal construction; and

Figure 5 is a sectional view taken on line 55 of Figure 3.

The electrically heated work creeper indicated generally by referencecharacter includes an elongated substantially rectangular body supportplatform 12 having pivotally secured on its underside adjacent each ofthe corners thereof caster wheels 14 to provide ready mobility of thedevice. On the upper side of platform 12 adjacent one of the ends is araised head rest 16 which may be substantially rectangular, as shown,for

example, in Figure 3, being padded with foam rubber 18 and being coveredby leather or any suitable plastic 19, in any suitable manner. The headrest element is hollow, as seen in Figures 3 and 5, and contains thereinthermostat structure and an electrical inlet plug, which will later bedescribed in greater detail.

The body support platform 12 includes two primary upper and lower panels20 and 22, respectively. The panels 20 and 22 are equal to the outerdimensions of the novel creeper, and are spaced in parallel relationshipby means of a plurality of longitudinal and transverse spacer strips 24and 26, respectively. Interposed between the spacer strips 24 and 26adjacent the main panels 20 and 22 is a suitable sealing or gasketmaterial 28. The aforementioned main panels and spacers cooperate toform an internal heat chamber 30 which is substantially water-tight.Covering substantially the entire area of chamber 30 is a suitableheating element 32 which is surrounded above and below and adjacent thesides and ends of the compartment by a suitable insulating material 34,such as fiber glass, which retains the heat of the heating element aswell as preventing dampness and shorting out of the heating element. Toprovide suitable rigidity and strength to the work creeper, transversereinforcing strips 36 are provided at spaced intervals along theunderside of the creeper adjacent panel 22, and longitudinal reinforcingstrips 38 are provided'on the outer edges of the upper panel 20. Thebody supporting portion of the creeper is assembled and secured togetherby means of suitable fastening elements, such as bolts with countersunkheads 40' and cooperating nuts 42. The head rest 16 is suitably securedto the portion 12 in any suitable manner, and may be provided withsealing means 44 of rubber or any suitable material to further ensureagainst the entrance of moisture inside the electrically heated creeper.On

the rear wall 46 of the head rest are included a power inlet plugindicated generally at 48 and an adjustable heat responsive rheostatindicated generally at 50. Although the aforementioned controls areindicated as being on the rear wall 46, it is readily apparent that thecontrols might be secured to either of the end walls or in any suitableposition on the work creeper. The power inlet plug is to be connected toa conventional male plug and flexible outlet cable of suflicient lengthto provide ready mobility of the creeper.

The adjustable heat responsive thermostat consists of a mounting bolt 52mounted in any suitable manner on the end wall 46 and having mountedthereon an adjusting support 54 of a suitable non-conducting material,such as plastic, having adjacent thereto a first conductor plate 56which extends toward the power inlet plug in juxtaposition with a firstcontact support arm 58 which has secured on its end a suitable contactelement 60. Separated from the first contact support arm is a secondbimetallic heat responsive second contact support arm 62 having securedthereon, in a position to contact contact element 60, a contact element64. In juxtaposition to the second contact support arm 62 is a suitablesecond conductor plate 66. Suitable insulators 68 are provided betweenthe metal conducting parts and a securing nut 70. It is to be understoodthat the bolt 52 is properly insulated away from any metal conductingparts. The power inlet plug 48, the first conductor plate and firstcontact support arm, second contact support arm and conductor plate andthe heater element 32 are conjacent the contact support arm 58 aninsulating portion 78 and at its opposite end on the exterior ascrewdriver receiving slot 80. The previously mentioned second heatresponsive bimetallic contact support arm, as indicated in Figure 5,includes the bimetallic portion 82 which, when subjected to excessiveheat above a predetermined temperature, tends to bend away from thecontact 60 separating the contact thereof from contact 64 to interruptthe flow of current to the heating element 32.

Thus, it can be seen I have provided a substantially automaticallyheating mechanics work creeper which has minimized the possibility ofshorting and shocks to the user thereof for the protection and comfortof the user.

Various positional directional terms, such as front or rear have only arelative connotation to aid in describing the device and are notintended to be interpreted as requiring any particular orientation withrespect to any external elements.

From the foregoing, the construction and operation of the device will bereadily understood and further explanation is believed to beunnecessary. However, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction shown and described, andaccordingly, all suitable modifications and equivalents may be resortedto, falling within the scope of the appended claims.

What is claimed as new is as follows:

1. A mobile work creeper constructed substantially of non-conductingmaterial comprising a creeper body including upper and lower panelssecured at their adjacent peripheral edges in spaced relation to definean inner compartment substantially coextensive with said panels, theupper panel including on its surface adjacent its opposite side edgeslongitudinally extending reinforcing strips extending the length of saidupper panel, the lower panel including on its lower surface a pluralityof reinforcing elements extending across the width of said lower panel,transverse and longitudinally extending spacer strips extending betweenthe inner surfaces of said panels around the entire perimeter thereof, asealing gasket interposed between said panels and both sides of saidspacer strips around the entire perimeter of said panels, fastenerelements extending through the reinforcing strips, spacer strips,sealing gasket, and panels along the longitudinal edge of said creeper,an electrical heating element comprising a plurality of longitudinallyextending bends of a single heating element comprising a plurality oflongitudinally extending bends of a single heating element contained insaid inner compartment, insulating means substantially enclosing theentire heating element on all sides for preventing heat loss andreducing the entrance of moisture in said compartment, a head restincluding a substantially hollow interior at one end on the top of thecreeper body, a power inlet plug secured on said head rest, and a heatresponsive thermostat connected in series to said power inlet plug andheating element.

2. A mobile work creeper as set forth in claim 1 wherein said head restincludes sealing means juxtaposed between a contacting portion of thehead rest and the creeper body, and sealing means are provided betweenthe adjacent upper and lower panels of the creeper body to substantiallyseal the inner portion of the head rest and inner compartment from theentrance of moisture and for retaining heat in said creeper body.

3. A mobile work creeper as set forth in claim 2 wherein said heatresponsive thermostat is manually adjustable by means of a manuallyoperable element accessible on the outside of said head rest.

4. A mobile work creeper as set forth in claim 3 wherein said heatresponsive thermostat includes a heat responsive bimetallic temperaturecontrol element operable to contact an adjacent conducting element formaintaining controlled temperature in said work creeper.

References Cited in the file of this patent UNITED STATES PATENTS1,704,127 Hicks Mar. 5, 1929 2,475,266 Williams July 5, 1949 2,587,731Irving Mar. 4, 1952 2,613,307 La Mirand Oct. 7, 1952

